The present invention relates to a storage apparatus in which the writing and reading of information are possible, and more particularly to a storage apparatus in which a change in alignment of several atoms is used as the unit of stored information.
Conventional storage devices include a DRAM (Dynamic Random Access Memory) in which information is stored in accordance with whether or not electric charges are stored in a capacitor and an SRAM (Static Random Access Memory) in which information is stored by a flip-flop circuit. In order to store one bit of information, the SRAM and DRAM require areas of about 100 nm.sup.2 and 25 nm.sup.2, respectively. Techniques of writing characters on molecules with a very large molecular weight, e.g., adbenzene or a bulk surface are known for the realization of storage devices in which storage or recording with higher density is possible. In the conventional storage device such as SRAM or DRAM, the realization of a further high storage density is difficult due to the limitations of manufacturing techniques or the like.
In order to overcome such limitations, a technique may be considered in which an atom(s), which is the constituent unit or element of a substance, is used a a unit cell for storage of information.